Phagocytosis

The first line of defence against disease is to prevent the entry of pathogens. The skin provides the main physical barrier, but the thinner coverings, such as the epithelial layer in the lungs, also secrete mucus to provide a…

Phagocytosis

The first line of defence against disease is to prevent the entry of pathogens. The skin provides the main physical barrier, but the thinner coverings, such as the epithelial layer in the lungs, also secrete mucus to provide a…